lua, 222 bytes

Result

WA

Duration

469ms

Code [DL]

a={}for k=1,4 do for s in string.gmatch(io.read(),"[^%s]+")do a[#a+1]=s end end
for z=1,9 do a[z]=a[z]-a[9+(z+1)%3]end
print(math.floor((a[8]*(a[1]*a[6]-a[4]*a[3])+a[7]*(a[5]*a[3]-a[2]*a[6])+a[9]*(a[4]*a[2]-a[1]*a[5]))/6))

stdin

42 97 10
72 65 40
62 87 82
12 43 07

stdout

3679

stderr

strace